冷冻砂                                                 

Innovations In High Performance Cryogenic Deflashing Compounds

Technical advances in the design of cryogenic shotblasting equipment have enabled the process of deflashing complex, precision rubber mouldings to be carried out with consistent and reliable results. Increased thermal insulation, accurate blasting parameters and a more efficient distribution of blast media have all contributed to reduced costs, higher quality and improved throughput speeds.

One area of the deflashing process that has failed to keep pace with these developments is the continued use of polycarbonate resins as the blasting media despite the considerable advances in polymer engineering over this period. At room temperature polycarbonate resin is a tough, resilient material with good impact strength and a high resistance to surface abrasion. However once the temperature falls to sub zero levels, the polymer becomes brittle and starts to breakdown into dust, reducing the shotblasting efficiency.

Once the temperature reaches -30°C the blast media has lost almost 70% of its original impact strength and this rapid deterioration in mechanical properties continue to -80°C when the polymer structure can fail completely.

While the addition of plasticizers can overcome many of these problems, the resulting blast media is soft and inefficient with poor abrasion resistance and low kinetic energy.

These inefficiencies in the deflashing process require excessive use of blast media, liquid nitrogen consumption and blasting wheel speeds to compensate for this poor performance.

Recent innovations in molecular engineering have enabled base polycarbonate resins to be crosslinked with various fluoro polymers that withstand the challenging conditions demanded in high performance cryogenic shotblast applications and equipment. Increased performance greater efficiencies and reduced cost combine with improvements in quality standards exceeding those found in standard blast compounds.